Harmonic and intermodulation performance of metallic carbon nanotube (MCNT) and complementary carbon nantube field effect transistor (CNTFET) amplifier

This paper presents a simple mathematical model for the output-voltage (current)/ input-voltage characteristic of the carbon nanotube field effect transistor (CNTFET) complementary inverting amplifier and the metallic carbon nanotube (MCNT) interconnect. The model, basically a Fourier series, yields closed-form expressions for the amplitudes of the harmonic and intermodulation components of the output voltage (current) resulting from a multisinusoidal input voltage. The special case of a two-tone equal-amplitude input voltage is considered in detail. The results show that the harmonic and intermodulation performance of the complementary CNTFET-based inverting amplifier and the MCNT interconnect is strongly dependent on the values of the amplitudes of the input tones with the third-order intermodulation component dominating over a wide range of the input voltage amplitudes. The results also show that while the harmonics may exhibit minima, the intermodulation products are almost monotonically increasing with the increase in the input voltage amplitude and exhibit no minima.